Manufacturing method of electrode for rechargeable battery

Abstract

A method of manufacturing an electrode of a rechargeable battery, the method including a first step of injection molding a plate-shaped electrode sheet in an injection mold with an electrode mixture that is input into an injection device, resulting in a molded electrode sheet, a second step of moving the molded electrode sheet onto a metal substrate and a third step of laminating the metal substrate and the molded electrode sheet.

What is claimed is: 
     
         1 . A method of manufacturing an electrode of a rechargeable battery, the method comprising:
 a first step of injection molding a plate-shaped electrode sheet in an injection mold with an electrode mixture that is input into an injection device, resulting in a molded electrode sheet;   a second step of moving the molded electrode sheet onto a metal substrate; and   a third step of laminating the metal substrate and the molded electrode sheet.   
     
     
         2 . The method of manufacturing the electrode of the rechargeable battery as claimed in  claim 1 , wherein, in the third step,
 the metal substrate is cut,   the molded electrode sheet is laminated on one surface of the metal substrate in a press device, and   the molded electrode sheet is laminated to another surface of the metal substrate.   
     
     
         3 . The method of manufacturing the electrode of the rechargeable battery as claimed in  claim 1 , wherein, in the third step,
 the metal substrate is cut, and   the molded electrode sheet is disposed on both sides of the metal substrate in a press device and laminated.   
     
     
         4 . The method of manufacturing the electrode of the rechargeable battery as claimed in  claim 1 , wherein:
 for a positive electrode, the electrode mixture includes a positive electrode active material, a binder, a conductive material, and a curing agent, and   a ratio of positive electrode active material:binder:conductive material:curing agent is 96.9:1.8:2:2.   
     
     
         5 . The method of manufacturing the electrode of the rechargeable battery as claimed in  claim 1 , wherein for a positive electrode, based on 100 wt % of the electrode mixture, the electrode mixture includes:
 85.0 wt % to 98.5 wt % of a positive electrode active material,   0.5 wt % to 5.0 wt % of a binder,   0.5 wt % to 5.0 wt % of a conductive material, and   0.5 wt % to 5.0 wt % of a curing agent.   
     
     
         6 . The method of manufacturing the electrode of the rechargeable battery as claimed in  claim 5 , wherein:
 the binder assists in the bonding of the positive electrode active material and the conductive material and to the metal substrate, and   is formed of one of polyvinylidene fluoride, polyvinyl alcohol, carboxymethyl cellulose, starch, hydroxypropyl cellulose, regenerated cellulose, polyvinylpyrrolidone, tetrafluoroethylene, polyethylene, polypropylene, ethylene-propylene-diene terpolymer (EPDM), sulfonated EPDM, styrene-butadiene rubber, and fluorine rubber.   
     
     
         7 . The method of manufacturing the electrode of the rechargeable battery as claimed in  claim 5 , wherein the conductive material includes a non-linear first conductive material and a linear second conductive material. 
     
     
         8 . The method of manufacturing the electrode of the rechargeable battery as claimed in  claim 7 , wherein the non-linear first conductive material includes at least one of Denka black and carbon-based materials, wherein the Denka black and carbon-based materials include carbon black, acetylene black, Ketjen black, channel black, furnace black, lamp black, thermal black, and Super-P. 
     
     
         9 . The method of manufacturing the electrode of the rechargeable battery as claimed in  claim 8 , wherein:
 the first conductive material has an average particle diameter of 50 nm to 110 nm,   the second conductive material is a linear carbon nanotube manufactured through a wet grinding process, and   an average length of the linear carbon nanotube is 1 μm to 5 μm.   
     
     
         10 . The method of manufacturing the electrode of the rechargeable battery as claimed in  claim 5 , wherein the curing agent includes one of an epoxy-based resin and a phenol-based resin. 
     
     
         11 . The method of manufacturing the electrode of the rechargeable battery as claimed in  claim 10 , wherein the epoxy-based resin includes at least one of bisphenol A epoxy resin, bisphenol F epoxy resin, bisphenol S epoxy resin, bisphenol epoxy resin, phenolic novolac epoxy resin, cresol novolac epoxy resin, bisphenol A novolac epoxy resin, bisphenol F novolac epoxy resin, phenolic salicylic aldehyde novolac epoxy resin, cycloaliphatic epoxy resin, aliphatic chain epoxy resin, glycidyl ester type epoxy resin, and modified resins thereof. 
     
     
         12 . The method of manufacturing the electrode of the rechargeable battery as claimed in  claim 10 , wherein the phenolic resin includes at least one of bisphenol F, bisphenol A, bisphenol S, polyvinyl phenol, phenol, cresol, alkyl phenol, catechol, novolac resin, and halide substitutes thereof. 
     
     
         13 . The method of manufacturing the electrode of the rechargeable battery as claimed in  claim 1 , wherein in the second step, the electrode sheet, which is molded and separated from the injection mold and then freely falls or is moved by a gripper, is moved onto the metal substrate. 
     
     
         14 . The method of manufacturing the electrode of the rechargeable battery as claimed in  claim 1 , wherein for a negative electrode, the electrode mixture includes:
 85.0 wt % to 98.5 wt % a negative electrode active material,   0.5 wt % to 5.0 wt % of a binder,   0.5 wt % to 5.0 wt % of a conductive material, and   0.5 wt % to 5.0 wt % of a curing agent.   
     
     
         15 . The method of manufacturing the electrode of the rechargeable battery as claimed in  claim 1 , wherein in the first step,
 a rectangular space is formed with an upper mold and a lower mold of the injection mold, and   the electrode sheet is molded into a plate-shaped rectangular parallelepiped.   
     
     
         16 . The method of manufacturing the electrode of the rechargeable battery as claimed in  claim 15 , wherein in the first step, an overall thickness of the electrode sheet is uniformly molded. 
     
     
         17 . The method of manufacturing the electrode of the rechargeable battery as claimed in  claim 1 , wherein in the first step, a chamfer is molded, in which a thickness becomes gradually thinner on an outer portion of one surface of the electrode sheet, by a convex round region at a corner of an inner space of a lower mold among an upper mold and the lower mold of the injection mold. 
     
     
         18 . The method of manufacturing the electrode of the rechargeable battery as claimed in  claim 1 , wherein in the third step,
 the metal substrate is unwound and continuously supplied, and   the electrode sheet is laminated and rewound on both sides of the metal substrate in a press device.